You are what you eat.

Quick Summary

  • Vitamin A: Take after breakfast/lunch. Fat-soluble; 2000-5000 IU daily is safe.
  • Vitamin B Complex: Water-soluble, can be taken anytime, no need for fat. Keep daily intake under 50 mg.
  • Vitamin D: Fat-soluble, take with meals. 5000 IU daily.
  • Fish Oil: One capsule each with breakfast and lunch to aid absorption of other supplements.
  • Magnesium L-Threonate / Glycinate: ~2000 mg per capsule, one with breakfast, two an hour before sleep.

Why Supplement?

Modern urban life means long indoor hours, irregular meals, and lack of sunlight — all leading to serious nutritional imbalances. A recent checkup revealed I was severely deficient in Vitamin D, which pushed me to research modern nutrition in depth.

Even with a balanced diet, modern farming and food processing have reduced nutrient density. Depleted soil, over-processing, and long-distance transport and storage all contribute to nutrient loss.

While working on better eating habits, sensible supplementation is a practical way to maintain health.

Disclaimer

This article is for reference only and does not constitute medical advice. Everyone's needs differ. Ideally, get tested and adjust your regimen based on your actual levels. Excessive intake of certain vitamins (especially fat-soluble A, D, E, K) can be toxic.

Always consult a doctor or registered dietitian before starting any supplement regimen, especially if you have chronic conditions, take medication, or are pregnant/nursing.

Finally, supplements are not a substitute for a balanced diet, regular exercise, good sleep, and sunlight.

Key Terms

  • Fat-soluble vitamins: A, D, E, K. Require bile and fat for absorption. Can be stored in the body, so overdosing can cause toxicity.
  • Water-soluble vitamins: B complex and C. Not stored in significant amounts; excess is excreted in urine.
  • IU (International Unit): A standard measure of biological activity.
    • Vitamin A: 1 IU = 0.3 mcg retinol
    • Vitamin D: 1 IU = 0.025 mcg cholecalciferol (D3)
    • Vitamin E: 1 IU ≈ 0.67 mg d-alpha-tocopherol (natural)

Vitamin A

Recommended intake: 800-1000 mcg RAE daily. 2000-5000 IU is safe. Don't exceed 10,000 IU/day.

Timing: After breakfast or lunch. Fat-soluble, needs fat for absorption.

Deficiency: Night blindness, dry eyes, skin issues, weakened immunity.

Food sources: Liver, dairy, egg yolk, fish liver oil. Plant sources (carrots, sweet potatoes, spinach) contain beta-carotene which converts poorly — roughly 1/12 the efficiency of animal sources.

💊 My regimen: 5000 IU daily, after lunch. Brand: Shuangjing Vitamin A softgels 5000 IU.

Vitamin B Complex

Recommended intake: Don't take individual B vitamins alone — take a complete B complex. Keep total daily intake under 50 mg.

Timing: Water-soluble, can be taken anytime. No fat needed.

B vitamins work together as enzyme cofactors. Taking the full spectrum is more effective than singles.

B1 (Thiamine)

Deficiency: Beriberi (muscle weakness, edema, heart failure), nerve inflammation.

Sources: Brown rice, whole wheat, oats, soybeans, pork, sunflower seeds.

B2 (Riboflavin)

Deficiency: Mouth ulcers, cheilitis, glossitis, light sensitivity, blurred vision.

Sources: Liver, dairy, eggs, leafy greens, legumes.

B3 (Niacinamide)

Deficiency: Pellagra, skin irritation, diarrhea, dizziness, fatigue. Poor capillary circulation (cold hands/feet).

Sources: Fish, poultry, liver, whole grains, peanuts, mushrooms.

B5 (Pantothenic Acid)

Deficiency: Rare. Fatigue, irritability, sleep disturbances, nausea.

Sources: Nearly all foods — liver, chicken, eggs, whole grains, broccoli, avocado.

B7 (Biotin)

Deficiency: Rare. Hair loss, skin inflammation, brittle nails.

Sources: Liver, egg yolk, milk, mushrooms, nuts. Gut bacteria also synthesize biotin.

B9 (Folate)

Deficiency: Anemia, fatigue, birth defects (neural tube defects).

Sources: Liver, eggs, leafy greens, legumes, citrus. Easily destroyed by cooking.

Important: Women should supplement folate before and during pregnancy.

B12 (Cobalamin)

Deficiency: Megaloblastic anemia, neurological issues (numbness, memory loss), fatigue.

Sources: Almost exclusively animal products — liver, meat, fish, eggs, dairy. Vegans and elderly are at risk.

💊 My regimen:

  • B Complex (B1/B2/B3/B6), 50 mg daily, after breakfast.
  • Extra B9 (Folic acid), 0.4 mg daily, with breakfast.

Vitamin C

Recommended intake: 100 mg is the minimum. 200 mg daily is better, 500 mg is optimal, 1000 mg when sick.

Timing: Water-soluble, anytime. Split doses if taking large amounts — the body has a limited absorption ceiling per dose.

Deficiency: Scurvy, weakened immunity, dry skin, fatigue, bleeding gums.

Food sources: Citrus, kiwi, strawberries, bell peppers, broccoli, leafy greens.

💊 My regimen: 100 mg daily, anytime. Brand: Northeast Pharma Vitamin C 100 mg tablets.

Vitamin D

Vitamin D is essential for calcium homeostasis, bone health, and immune function.

Timing: Take with a meal containing fat for best absorption. Don't take at night — it can interfere with sleep.

Deficiency: Rickets, osteoporosis, weakened immunity, bone pain, muscle weakness.

Sources: Sunlight is the primary source (30 min/day). Also found in fish liver oil, salmon, egg yolk. Very hard to get enough from food alone.

Recommended intake: 800 IU maintenance. If deficient: 2000-5000 IU. If severely deficient: 5000-10,000 IU for a month, then retest.

Important notes:

  • D3 (cholecalciferol) is better absorbed than D2.
  • Fat-soluble — can accumulate, but toxicity is rare below 5000 IU/day.
  • Normal range: 30-100 ng/ml (25-hydroxyvitamin D). Aim for ~50 ng/ml.
  • Below 30 ng/ml: supplement 5000 IU/day, retest after a month.
  • Below 10 ng/ml: 5000-10,000 IU/day for a month, then retest.
  • Long-term high-dose D3 (>5000 IU for over a year) requires K2 and magnesium. D3 opens the door for calcium, K2 directs calcium to bones, magnesium is a cofactor for D3 activation.

💊 My regimen: 5000 IU daily, after breakfast with fatty food. Brand: Naturewise Vitamin D3 5000 IU.

Vitamin E

Recommended intake: 15-20 mg daily.

Timing: With meals. Fat-soluble.

Deficiency: Neurodegenerative issues, muscle weakness, vision problems, weakened immunity.

Food sources: Vegetable oils, nuts and seeds (almonds, sunflower seeds), leafy greens.

💊 My regimen: A handful of nuts daily, or 1 capsule (100 mg) after lunch. Brand: Shuangjing Vitamin E 100 mg softgels.

Vitamin K

Timing: With meals. Fat-soluble.

Deficiency: Rare in adults. Bleeding tendency, coagulation issues.

Food sources: K1 from leafy greens, K2 from liver and fermented foods (natto, cheese).

💊 My regimen: K2 (MK-7), 100 mcg daily, taken with Vitamin D3. MK-7 has a longer half-life and better bioavailability than MK-4.

Other Supplements

Fish Oil

2 capsules daily, one each with breakfast and lunch.

Brand: Viva Naturals Fish Oil (EPA 750 mg + DHA 284 mg + DPA 25 mg).

Coenzyme Q10

Mitochondrial fuel. 100 mg daily, after lunch with fish oil.

Brand: Doctor's Best High Absorption CoQ10 (with BioPerine for 30%+ better absorption).

Note: May be stimulating — avoid taking at night.

Lutein

1 capsule daily, after breakfast. Pair with Vitamin C for better absorption.

Brand: Blackmores Lutein Defense (10 mg lutein + 2 mg zeaxanthin). Don't take at night.

Magnesium Glycinate

D3 activator and sleep aid. ~200 mg, one hour before sleep.

Why: Long-term D3 supplementation depletes magnesium. Glycinate form is well-absorbed, gentle on the stomach, and promotes relaxation and sleep.

Avoid: Magnesium oxide — poor absorption, causes diarrhea.

Zinc

Three times daily, one tablet each time.

Brand: Nandao Zinc Gluconate 70 mg tablets. Absorption rate is low, so higher dosage is needed.

Daily Schedule

  • After breakfast: Vitamin D3+K2, B Complex + Folate, Vitamin C, Lutein, Fish Oil
  • After lunch: Fish Oil, CoQ10, Vitamin A, Vitamin E
  • Throughout the day: Zinc
  • One hour before sleep: Magnesium Glycinate

Original article (Chinese): Daily Nutrition Supplements